10' wu, 10' cd. You are going to run 8x 800 at the same time as your goal marathon pace. For example, if you want to run a 4:05 marathon, you will run the 800s in 4:05. If you are going to run these without knowing the distance, then run them at LT -5 beats. Your recovery is equal to your work time. 4:05 work time equals 4:05 recovery time.